wiring harness

uneasy rider

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What wiring harness(s) would be needed to completely re-wire a 75 MK lll ? I have seen prices for a "main" harness, Are there sub harnesses needed?
Thanks in advance.
 
You could build your own if you aren’t going for everything original. That’s what I did — went negative ground as well.
 

If it has electronic ignition then you might be better off making the ignition harness section to suit the electronic ignition.
You may also have to make up the (normally white) wires from the ignition switch to the console as they don't seem to come with the headlamp harness or console sections.
Possibly, depending on the type of ignition.
 
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If you are running an electronic ignition system, the ignition wiring harness probably won't be required, wasn't in my case.
 
What equipment has your machine got fitted? Electronic ign, modern voltage regulator, 3 phase alternator, etc? Unless you are a stickler for originality it is far better to, either make your own harness or get someone to do it for you. It will be far more reliable as you can get rid of the bunch of connectors under the tank and move the switchgear connectors to inside the headlamp shell and at the same time use better connectors for the switchgear. (the original pin connectors are shite) With the cost of the various harnesses needed (for original) in L.A.B.s list (over $500) it wont be a lot more (or quite possibly cheaper) to have your harness made. Another thing to consider is the wrapping of the harness/loom. Avoid like the plague the cloth wrapped looms, It makes the loom far too stiff to get around the machine and the cloth wrapping holds all the oil and shite the machine attracts.
 
MK3 wiring is a whole lot more complicated than all the earlier models. It is easier to just buy a harness. One big advantage of making your own harness is the ability to remove all the charging wires and ignition wires and the many ground wires. Suddenly the bundle is thinned out quite a bit. Perhaps if the new harness was carefully laid out and unwrapped, the wires could be stripped out. To further reduce the wires a Tri-Spark ignition could be used
 
MK3 wiring is a whole lot more complicated than all the earlier models. It is easier to just buy a harness. One big advantage of making your own harness is the ability to remove all the charging wires and ignition wires and the many ground wires. Suddenly the bundle is thinned out quite a bit. Perhaps if the new harness was carefully laid out and unwrapped, the wires could be stripped out. To further reduce the wires a Tri-Spark ignition could be used
I rebuilt my existing harness. I kept all the main sub-harness connectors so I could unplug it when needed. Adapted/wired it to my Trispark ignition and rect/reg. Removed the assimilator, capacitor, zener diode, power outlet wires, and finally the extra ground wires that were no longer needed. I added an ICM Charge Light in lieu of the assimilator. I wrapped it all in non-adhesive PVC harness tape (per Greg M’s advice). Used correct color coded wires where old ones needed replacing along with British bullet connectors where needed. It came out like new, looking like the stock harness. Wasn’t hard.
 
MK3 wiring is a whole lot more complicated than all the earlier models. It is easier to just buy a harness. One big advantage of making your own harness is the ability to remove all the charging wires and ignition wires and the many ground wires. Suddenly the bundle is thinned out quite a bit. Perhaps if the new harness was carefully laid out and unwrapped, the wires could be stripped out. To further reduce the wires a Tri-Spark ignition could be used
Depending on what type of Loom you want to unwrap. The modern cloth wrapped looms have the cloth tape superglued at the start and finishes. Making unwrapping a considerable bind. The ground wires are there so you don't rely on the frame as the return path and with the modern penchant for powder coating, having a reliable return path is paramount.
 
Original Commando looms were raped with tape not cloth, I brought a taped Mk3 loom from Andover though the wires for the assimilator were not in the correct position.
 
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